Preliminary investigation of high-water content dredged sediment treated with chemical-physical combined method at low cement content.

Autor: Mastoi AK; Institute of Geotechnical and Underground Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.; Department of Civil Engineering, Quaid-E-Awam University of Engineering, Sciences and Technology, Sindh, 67450, Pakistan., Bhanbhro R; Department of Civil Engineering, Quaid-E-Awam University of Engineering, Sciences and Technology, Sindh, 67450, Pakistan., Traore AF; Institute of Geotechnical and Underground Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China. abdoulfatah@hust.edu.cn., Oad M; Department of Civil Engineering, Quaid-E-Awam University of Engineering, Sciences and Technology, Sindh, 67450, Pakistan., Zardari S; Department of Civil Engineering, Quaid-E-Awam University of Engineering, Sciences and Technology, Sindh, 67450, Pakistan., Jhatial AA; Department of Civil Engineering, Mehran University of Engineering and Technology, Shaheed Zulfiqar Ali Bhutto Campus, Khairpur Mirs', Sindh, Pakistan.
Jazyk: angličtina
Zdroj: Environmental science and pollution research international [Environ Sci Pollut Res Int] 2022 May; Vol. 29 (22), pp. 32763-32772. Date of Electronic Publication: 2022 Jan 12.
DOI: 10.1007/s11356-021-18167-x
Abstrakt: Land reclamation projects are increasingly incorporating dredged sediment from waterways. The high water content of dredged sediment is a major issue, making the dewatering process difficult and time-consuming. The chemical-physical combined method (CP) is therefore used in this study, which simultaneously uses vacuum dewatering by utilising vacuum pressure (VP) in conjunction with prefabricated horizontal drain (PHD) and Portland cement (PC)-based solidification/stabilisation (SS), thereby significantly reducing the duration of treatment of DS with high water content. The effectiveness and feasibility of the chemical-physical combined method with Portland cement (PC) as a binder are evaluated and compared with the traditional PC-based solidification/stabilisation (SS) method. A number of experimental tests were performed to accomplish the objectives of the study, such as unconfined compressive strength (USS), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The experimental results indicated that the CP method showed better performance compared to the traditional SS method in treating high water content DS at low cement content. The water content of DS treated with the chemical-physical combined method was reduced by half in just about 3 days, and the final rate of settlement was 2.9 times higher than with SS-treated DS. The USC results showed that the strength of CP cases was 4.8 times higher than SS-treated DS after 56 days of curing age. The microstructural tests revealed the development of CSH and CASH as major hydration products of both CP and SS cases. Moreover, CP cases exhibited a densely stabilised matrix compared to SS cases.
(© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
Databáze: MEDLINE
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